Various types of presses have previously been employed to produce thin metal containers, such as those of the cylindrical drawn metal type usually having greater longitudinal dimensions than lateral dimensions. However, such prior art machines have tended to have certain drawbacks: e.g., undue complexity, excessive space requirements of operation and contamination control, and excessive power consumption. More particularly, such processes require unnecessary transfer of partially formed containers from one press to another during multiple drawing thus subjecting same to damage.
Attempts have been made to improve upon the above-noted deficiencies; for example, the presses described in U.S. Pat. Nos. 3,683,665 and 4,026,226, the latter being an inverted press. It is common to strip feed a press by angling a stack of strips so that the top strip can slide from the stack with the aid of gravity. It is uncommon to feed metal strips into a drawing press by means of lifting strips off a horizontally disposed stack and then individually feeding them. More particularly, a conveyor and elevator system adapted to provide a continual supply of specifically positioned strips for a lifting and feeding means is unique. The invention includes means for prelubricating the strip before forming and in that regard the U.S. Pat. No. 2,302,856 shows a reciprocating die for pumping lubricant while U.S. Pat. No. 2,107,577 shows a system for oiling near a cutting edge. None of the art include a technique which confines the lubricant to a specific predetermined area and include interrupting means to prevent lubrication when there is no strip. While it is common to progressively form drawn articles carried along a planar path through a progressive press; typical of such a progressive press is U.S. Pat. No. 1,725,330. However, so far as it is known, no presently available press affords the advantages of that of the instant invention, nor lends itself to the production of containers by the highly accurate, facile and economic method herein set forth. In progressive presses it is common to transfer the worked on article from station-to-station as it is progressively formed. Commonly, articles are transferred by carrying them with the scrap. In addition, complicated and heavy transfer mechanisms have been used to transfer individual semifinished articles as necessary, see for example U.S. Pat. Nos. 3,800,583 and 3,620,382. None of the prior art, however, include a light weight low inertia mechanism which pivots toward the containers and thus permits high-speed handling. Rarely do such presses include a system for handling semifinished articles which are so different in shape as to require additional means to maintain a portion of each within a common plane thereby facilitating handling. However, so far as it is known, no presently available press affords the advantages of that of the instant invention, nor lends itself to the production of containers by the highly accurate, facile and economic method herein set forth.
Accordingly, it is an object of the present invention to provide a novel press which is compact, and of relatively simple design, and which is economical, durable and convenient to use.
It is also an object of this invention to provide a novel press which is efficient and is capable of smooth, high-speed operation by means of minimizing the handling of the container necessary during forming.
A further object of this invention is to provide a novel press which minimizes contamination of the containers produced.
Still another object of the invention is to provide a novel press having the foregoing features and advantages, which is especially adapted for the production of drawn thin metal containers, and particularly, multiple drawn containers having a greater depth than diameter.
A more specific object of the invention is to provide a novel metal can drawing press in which operations of cupping, drawing, redrawing and trimming are accomplished with each stroke of the press with constant control over the position and location of the can during forming.
Yet another object is to provide a novel and facile method for the production of a drawn container by multiple forming and reforming of a drawn container on a press of the following description.